It can be thought of as a measure of how well the electrical components are insulated from each other and from the ground. In the lifecycle of a Photovoltaic (PV) plant, “Low Insulation Resistance” (ISO Fault) is one of the most common inverter error codes. Usually this leads to very small and harmless fault currents. On. The SolarEdge inverters to which this declaration applies (see below) are transformer-less inverters and therefore do not provide galvanic separation between DC and AC during operation. As per the standard DIN VDE 0126-1-1, they must not exceed a certain threshold before grid connection. The prescribed threshold for such PV plants during the creation of this standard was. The abbreviation for 'resistance' in physics is R, as in Ohm's law: V = I x R. For non-isolated inverters, it must be shut down and.
